1. Field of the Invention
The present invention relates to an X-ray computer tomography apparatus (CT (Computer Tomography)) including a circular orbit cone beam reconstruction function.
2. Description of the Related Art
Feldkamp et al. have proposed a circular orbit cone beam reconstruction method. In this reconstruction method, the two end portions of a reconstruction area include areas (mask areas) in which 360° projection data are not all obtained. The image quality of the mask areas is low. For this reason, the mask areas are excluded from image reconstruction processing and are not imaged. Even if mask areas are forced to be reconstructed, it is highly possible that distortion, a deterioration in shape reproducibility, and CT value shifts will occur.